feat: added TelephonyTransferCall in response message (#207)

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PiperOrigin-RevId: 414081404

Source-Link: googleapis/googleapis@0015848

Source-Link: https://github.com/googleapis/googleapis-gen/commit/31e432677be61ddf23eb394731dd33850cf8f62d
Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiMzFlNDMyNjc3YmU2MWRkZjIzZWIzOTQ3MzFkZDMzODUwY2Y4ZjYyZCJ9

Author: gcf-owl-bot[bot]

protos/google/cloud/dialogflow/cx/v3beta1/environment.proto

@@ -21,6 +21,7 @@ import "google/api/client.proto";
 import "google/api/field_behavior.proto";
 import "google/api/resource.proto";
 import "google/cloud/dialogflow/cx/v3beta1/test_case.proto";
+import "google/cloud/dialogflow/cx/v3beta1/webhook.proto";
 import "google/longrunning/operations.proto";
 import "google/protobuf/empty.proto";
 import "google/protobuf/field_mask.proto";

protos/google/cloud/dialogflow/cx/v3beta1/response_message.proto

@@ -164,6 +164,17 @@ message ResponseMessage {
     repeated Segment segments = 1;
   }
 
+  // Represents the signal that telles the client to transfer the phone call
+  // connected to the agent to a third-party endpoint.
+  message TelephonyTransferCall {
+    // Endpoint to transfer the call to.
+    oneof endpoint {
+      // Transfer the call to a phone number
+      // in [E.164 format](https://en.wikipedia.org/wiki/E.164).
+      string phone_number = 1;
+    }
+  }
+
   // Required. The rich response message.
   oneof message {
     // Returns a text response.
@@ -202,5 +213,9 @@ message ResponseMessage {
     // This message is generated by Dialogflow only and not supposed to be
     // defined by the user.
     MixedAudio mixed_audio = 13 [(google.api.field_behavior) = OUTPUT_ONLY];
+
+    // A signal that the client should transfer the phone call connected to
+    // this agent to a third-party endpoint.
+    TelephonyTransferCall telephony_transfer_call = 18;
   }
 }